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Asian Lady Beetle

Mulicolored Asian Lady Beetles

The Multicolored Asian Lady Beetle (Harmonia Axyridis) now makes its home in the United States. A native of Asia, this beneficial ladybug was imported in the early 1900's to help naturally control pest populations that were damaging such crops as alfalfa, pecan and citrus trees.

Over the past 15 years, USDA, the Forestry Commission, state and private agencies have released this ladybug in several locations in the Northeastern part of the US. The beneficial aspects of this ladybug have been quite useful in reducing the need for pesticides and have relieved the hardwood forests of many disease carrying aphids, mites and scale insects. **Releases are no longer taking place.***

The Asian Lady Beetle is much like the native species found through the United States. They are small, hemispherical in shape, and can be found with and without spots. Their colors may vary from red, and orange to a dull cream. However, unlike the native species, this ladybug can be quite aggressive. Masses of ladybugs have been known to swarm and even bite when seeking shelter for the winter months. In this regard, they have been an unwelcome guest for homeowners that don't find them to be good luck at all, but rather a nuisance.

The multi-colored Asian Lady Beetle goes through four stages in its life cycle. Female adult lady beetles lay eggs on plants near colonies of aphids, mites and scale insects. Yellow eggs are laid in clusters of varying numbers. After 3-7 days, the larva hatch out and begin searching for food. A larva will molt about four times (or shed its outer layer of skin) as it grows. Sometimes after the last molt, the larva will attach itself to the plant, becoming immobile as it is now in the pupa. Depending on the environmental factors, the new lady beetle will emerge from the case. It will look wet, shiny and often golden in color. The ladybug is very vulnerable during this time, as it waits for the exoskeleton to harden and dry revealing its true colors and markings.

Research Entomologists have been working diligently on methods to prevent ladybugs from entering the home and on ways to safely and effectively capture them once inside. Fortunately, ladybugs are not structure damaging insects. They will not eat home materials and will not lay eggs inside the home. Yet, if disturbed, the ladybug will stress, releasing a yellow, smelly substance from their joints. this is known as "reflex bleeding". It is a defensive mechanism for the insect to defend itself from predators.

The best preventative is to caulk cracks and crevices around doors and windows, pipes that enter the house and replace or repair damaged clap boards. Once ladybugs penetrate the home, they typically return year after year, knowing this was a good site to rest. Pheromones released by past ladybugs are detected by future generations. Also, the color of a home and the location are important factors. They tend to chose light colored homes that are nestled in forest or wooded areas.